Flexible drain for floating roofs



Ju e 17', 1947. R, c, U M 2,422,322-

FLEXIBLE DRAIN FOR FLOATING ROOFS Filed Sept. 14, 1944 2 Sheets-Sheet l INVENTOK 1264 72 GZZZm,

June 17, 1947. c, ULM 2,422,322

FLEXIBLE DRAIN FOR FLOATING ROOFS Filed Sept. 14, 1944 2 Sheets- Sheet 2 INENTOR.

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Patented June 17, 1947 FLEXIBLE DRAIN roe FLOATING noors Reign C. Ulm, East Chicago, Ind, assignor to Graver Tank &'Mfg. 00., 1110., East Chicago, End, a corporation of Delaware Application September 14, 1944, Serial No. 554,046

4 Claims.

The invention relates to floating roofs and has reference more particularly to an improved flexible drain for a floating roof for draining the roof through the tank to the outside thereof.

An object of the invention is to provide a flexible drain for a floating roof having swivel joints between sections of the drain and wherein one section will have movement in a vertical plane according to the movements of the roof with the other sections having movement in a horizontal plane.

With these and various other objects in view, the invention may consist of certain novel features of construction and operation, as will be more fully described and particularly pointed out in the specification, drawings and claims appended hereto.

In the drawings which illustrate an embodimerit of the device and wherein like reference characters are used to designate like parts Figure 1 is a vertical sectional view of a storage tank having a conventional floating roof and which is equipped with the flexible drain of the invention, the roof being shown in elevated position;

Figure 2 is a fragmentary sectional view taken substantially along line 22 of Figure 1;

Figure 3 is a vertical sectional view similar to Figure 1 illustrating the position of the flexible drain with the floating roof in its down position; and

Figure 4 is a fragmentary sectional view taken substantially along line 4-4 of Figure 3.

Referring to the drawings, the flexible drain of the invention is illustrated in connection with a conventional open top liquid storage tank identified by numeral H), the same comprising a cylindrical wall H and a bottom E2. The tank is adapted to contain volatile liquid such as gasoline for storage purposes and a roof floats upon and is sustained by the liquid in the tank. The said roof, indicated by numeral i l, essentially consists of a circular deck l5 formed of metal plates which may be suitably welded or otherwise secured to form a unitary structure, the diameter of which is less than that of the tank to permit movement of the roof within the tank. A circular depending flange [6 extends around the deck l5 and a bottom H is provided forming what is generally termed a pontoon roof. The parts of the pontoon roof are generally welded together to form an air-tight space within, thus giving the roof the desired buoyancy.

The structure for sealing the peripheral space between the cylindrical wall H of the tank and the depending flange it of the pontoon roof essentially comprises a flexible shoe or depending flexible skirt '26 extending completely around the inside of the tank so as to have contacting relation with said cylindrical wall thereof. The flexible shoe 2% is fastened at its upper end to the structural member 2! which is supported in position adjacent the tank wall by means of hangers '22. Said hangers are pivotally secured at 23 to the deck id of the pontoon roof and said hangers at their opposite ends have pivotal connection as at 2 3' with means secured to the structural member 2!. The upper end of the flexible skirt 28 is clamped between the structural member 25 and the metal toe 25. The sealing fabric 26 is likewise clamped between said parts with the opposite end of said sealing fabric being suitably secured as at 21 to the flange it of the pontoon roof. The gaseous vapors generated above the space surrounding the roof are thus trapped and confined in the space by the depending skirt 2i! and the sealing fabric 26. The pressure of the gaseous vapors above the liquid maintains said depending skirt in sealing contact with the tank shell and any tendency for the vapor pressure to lift the skirt out of the liquid is prevented by means of weights 23.

The flexible drain of the invention has connection with the vertical pipe 39, comprising the drain for the pontoon roof, and which extends through the bottom ll of the pontoon roof and through the circular deck I5 projecting a slight distance beyond both parts in opposite directions. A preferred construction of the circular deck l5 provides drainage from. the surface of the deck into the drain pipe 38 and which is thus conducted by said pipe through the pontoon roof into the flexible drain, which will now be described in detail.

Section 3] of the flexible drain is rotatably connected to the lower depending end of the drain pipe 35! by means of a one-way swivel connection 32. Section 33 of the flexible drain is pivotally secured to the outer end of Bi by means of a one-way swivel joint 34, and said section 33 at its opposite end is provided with a two-way swivel joint 35. The third section comprises the drain pipe 36 which has movement in a vertical plane in accordance with the movement of the floating pontoon roof. Movement of section 355 is in a vertical plane, whereas, sections 3i and 33 have movement in a horizontal plane, which is permitted by the two-way swivel joint 35 connecting the upper end of section 36 with section 33. The opposite lower end of section 35': is connected by means of a one-way swivel joint 31 to an outlet pipe 38 which extends through the tank wall II in the lower portion of the tank. From the outlet 33 the liquid draining through the flexible drain is conducted from the tank.

To eliminate excessive strain on swivel joints 34 and :35 it is desirable to support said joints from the pontoon roof. Section 3| has rotary movement with respect to the drain pi e 311 and since swivel 34 thus moves in a circle, an arcuate roller track 40 is secured to the undersurface of bottom 11 of the roof. The swivel 34 is suitably supported from the roller track in any manner which will permit movement in. a. horizontal plane of section 3 I of the flexible drain: As shown in the drawings, a roller 4| has rolling movement on the roller track and said roller" supports the swivel 34 by means of the connecting member 42. A roller track 43 is also provided for supporting the two-way swivel 35. To permit section 36 of the flexible drain to move in a vertical plane the roller track 43 extends substantially parallel with said'section and said track isalso secured to the undersurface of bottom ll of the pontoon roof. A roller carriage, indicated by 44, has rolling movement ontraok 33v and the carriage supports the two-way swivel 35 by means of supporting member 55. By supporting the swivel joints from the pontoon roof as above described excessive tension on the joints is eliminated and the possibility of leakage through the'joints is materially reduced.

The drain ofthe invention is flexible in that it permits movement of the floating roof within the tank. A change in the position of the roof results in a change in the relation of the sections ofthe drain to each other. Section 3| haslimited rotation around drain 3!? as a center. In a similar manner section 35 has pivotal movement on the outlet pipe 33. The intermediate section 33 has bodily movement from one extreme position, as shown in Figure 2, wherein the roof is at the top of the tank to an opposite extreme position, as shown in Figure 4, where the roof is located nearthe bottom of the tank. This bodily movement of section 33 is variable depending on the size of the tank, being aminimum for tanks of large diameter and of less height.

The invention is not to be limited to or by details of construction of the particular embodi ment thereofillustrated by the drawingsas various forms of the device will of course be apparent to those skilled in the art without departing from the spirit of the invention or the scope of the claims.

What is claimed is:

l. The'combination with'a floatingroof for a liquid storage tank, of a flexible drain therefor including a drain pipe extending substantially vertically through the floating roof and fixed thereto and dependingbelow the bottom thereof,

one section of said flexible drain'having'a swivel connection with'said drain pipe so that the section has horizontal rotary movement about'the drain pipe as a center, another section having a swivel connection with an outlet pipe'for said tankso as to move in a vertical planeasthe floating roof moves vertically, and a-third-section connecting said first mentioned section with the second mentioned section, said third section'of the flexible drain having horizontal bodily movement as the floating roof moves vertically.

2; The combination with-a floating roof for a liquid storage tank, ofa flexible drain therefor including a drain pipe extending substantially.

vertically through the floating roof and fixed thereto and depending below the bottom thereof, one section of said flexible drain having a swivel connection with said drain pipe so that the section has horizontal rotary movement about the drain pipe as a center, another section having a swivel connection with an outlet pipe for said tank ,so as to move in a. vertical plane as the floating roof moves vertically, a third section connecting said first mentioned section with the second mentioned section, said third section of the flexible drain havinghorizontal bodily movement as the floating roof moves vertically, and means supporting said sections of the flexible drain from the floating roof while permitting said sections to have movement.

3. The combination with a floating roof for a liquid storage tank, of a flexible drain therefor including a drain pipe extending substantially vertically through the floating roof and fixed thereto, and depending below the bottom thereof,

one-section of; said flexible drainhaving-a, swivel connectionwithsaid drainpipe so that the sec:

tion has horizontal rotary movement about the;

drain pipe as a center, another section having a swivel connection with an outlet pipefor said tank so as to move in a vertical plane asthe floating roof moves vertically, a third section havingja including a drain pipe extendin substantially vertically through the floating roof and; fixed thereto and dependingqbelow. the bottom thereof,

one section of saidflexible drain having aswivel' connection with said drain pipe. so that the'.se.ction has horizontal rotary movement about: the drain piper-as a center, a'section articulated-there:

with by means of'a, swivel connection. andv also.

having movement. in a,horizontal plane, another section of the flexible drain having, a.swivel connection at one end with an' outlet pipefor the; storage tank so as to move in a vertical plane as:

the floating roof moves vertically, a double. swivel connection located at the opposite: end: of, the;

last mentioned section and connectinggthe' same with the second mentioned section, andmeans supporting saidzdouble swivel fromthe floating roof to eliminate excessive strain: on said-part,.

said supporting. means includin a carriage; having rolling; contact on track guides fixed'to, the floating roof;

REIGNC; ULM..

- REFERENCES CITED.

The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,056,857 Inbodenetal. Oct. 6, 1936 l;'761,'700' Bailey June-3; 1930 2,007,193 Griffin July. 9., 1935 1,857,362 Day. May 10, 1932. 1,897,779 Wiggins Feb. 14; 1,933 1,840,587 Kimbell Jan. 12, 1932 1,819,401 Bailey Aug. 18 1931' 

